On 2021/2/24 1:45 下午, Jason Wang wrote:
During procss_tx_desc(), driver can try to chain data descriptor with
legacy descriptor, when will lead underflow for the following
calculation in process_tx_desc() for bytes:
if (tp->size + bytes > msh)
bytes = msh - tp->size;
This will lead a infinite loop. So check and fail early if tp->size if
greater or equal to msh.
Reported-by: Alexander Bulekov <[email protected]>
Reported-by: Cheolwoo Myung <[email protected]>
Reported-by: Ruhr-University Bochum <[email protected]>
Cc: Prasad J Pandit <[email protected]>
Signed-off-by: Jason Wang <[email protected]>
---
hw/net/e1000.c | 4 ++++
1 file changed, 4 insertions(+)
Applied.
Thanks
diff --git a/hw/net/e1000.c b/hw/net/e1000.c
index d8da2f6528..4345d863e6 100644
--- a/hw/net/e1000.c
+++ b/hw/net/e1000.c
@@ -670,6 +670,9 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp)
msh = tp->tso_props.hdr_len + tp->tso_props.mss;
do {
bytes = split_size;
+ if (tp->size >= msh) {
+ goto eop;
+ }
if (tp->size + bytes > msh)
bytes = msh - tp->size;
@@ -695,6 +698,7 @@ process_tx_desc(E1000State *s, struct e1000_tx_desc *dp)
tp->size += split_size;
}
+eop:
if (!(txd_lower & E1000_TXD_CMD_EOP))
return;
if (!(tp->cptse && tp->size < tp->tso_props.hdr_len)) {
